Timer1 interrupt is hit but IRQHandler not executed
Hi,
I've written a sample code for LPC2378 (simulation mode using keil) to generate timer1 interrupt in IRQ mode.
Upon T1MR0 match, timer1 is generating interrupt but the IRQHandler is not invoked instead the control is transfer to else where in the program.
I've place a break point but no luck in IRQHandler.
Please help me in resolving this issue:
void InitTimer1() {
/* Timer1 and Preset disabled */
T1TCR = 0x00;
/* Timer Counter register, after PR is reset, this inc by 1 */
T1TC = 0x00;
/* Prescalar register! Max value for prescalar counter */
T1PR = 0xFFFF;
/* Prescale Counter register */
T1PC = 0x0;
/* End user has to fill in the match value */
T1MR0 = 0x222;
/* Reset TC and interrupt on match */
T1MCR = 0x03; /* 0000 0000 0000 0011 */
}
void enable_IRQ(void)
{ int tmp;
__asm
{
MRS tmp, CPSR
BIC tmp, tmp, #0x80
MSR CPSR_c, tmp
}
}
void InitVIC() {
VICIntSelect &= ~(1L<<5); /* Timer 1 selected as IRQ */
VICVectAddr5 = (unsigned long )IRQHandler;
VICVectPriority5 = 0x05;
VICIntEnable |= 0x20; /* Timer 1: (bit 5) interrupt enabled */
}
__irq void IRQHandler(void)
{
unsigned static int i = 0;
T1IR = 0x01; /* Clear Timer1 MR0 interrupt */
IOSET0 = ~ (1 << (i+1));
if ( i == 32)
i = 1;
i++;
VICVectAddr = 0x00000000; /* Dummy write to ACK the VIC */
}
int main() {
InitPLL();
EnableMAM();
SetPeripheralClock();
InitGPIO();
enable_IRQ();
InitTimer1();
InitVIC();
/* Timer1 and Preset Enabled */
T1TCR = 0x01;
/* Rest of the code */
while (1);
}
The startup.s file has the following:
Vectors LDR PC, Reset_Addr
LDR PC, Undef_Addr
LDR PC, SWI_Addr
LDR PC, PAbt_Addr
LDR PC, DAbt_Addr
NOP ; Reserved Vector
; LDR PC, IRQ_Addr
LDR PC, [PC, #-0x0120] ; Vector from VicVectAddr
LDR PC, FIQ_Addr
